[PATCH] sched: remove balance on clone

This removes balance on clone capability altogether.  I told Andi we wouldn't
remove it yet, but provided it is in a single small patch, he mightn't get too
upset.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/sched.h

@@ -574,11 +574,10 @@ do { if (atomic_dec_and_test(&(tsk)->usage)) __put_task_struct(tsk); } while(0)
 
 #define SD_BALANCE_NEWIDLE	1	/* Balance when about to become idle */
 #define SD_BALANCE_EXEC		2	/* Balance on exec */
-#define SD_BALANCE_CLONE	4	/* Balance on clone */
-#define SD_WAKE_IDLE		8	/* Wake to idle CPU on task wakeup */
-#define SD_WAKE_AFFINE		16	/* Wake task to waking CPU */
-#define SD_WAKE_BALANCE		32	/* Perform balancing at task wakeup */
-#define SD_SHARE_CPUPOWER	64	/* Domain members share cpu power */
+#define SD_WAKE_IDLE		4	/* Wake to idle CPU on task wakeup */
+#define SD_WAKE_AFFINE		8	/* Wake task to waking CPU */
+#define SD_WAKE_BALANCE		16	/* Perform balancing at task wakeup */
+#define SD_SHARE_CPUPOWER	32	/* Domain members share cpu power */
 
 struct sched_group {
 	struct sched_group *next;	/* Must be a circular list */
@@ -759,7 +758,7 @@ extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
 #else
  static inline void kick_process(struct task_struct *tsk) { }
 #endif
-extern void FASTCALL(sched_fork(task_t * p, unsigned long clone_flags));
+extern void FASTCALL(sched_fork(task_t * p));
 extern void FASTCALL(sched_exit(task_t * p));
 
 extern int in_group_p(gid_t);

kernel/fork.c

@@ -1030,7 +1030,7 @@ struct task_struct *copy_process(unsigned long clone_flags,
 	p->pdeath_signal = 0;
 
 	/* Perform scheduler related setup */
-	sched_fork(p, clone_flags);
+	sched_fork(p);
 
 	/*
 	 * Ok, make it visible to the rest of the system.

kernel/sched.c

@@ -874,30 +874,10 @@ static int find_idlest_cpu(struct task_struct *p, int this_cpu,
  * Perform scheduler related setup for a newly forked process p.
  * p is forked by current. The cpu hotplug lock is held.
  */
-void fastcall sched_fork(task_t *p, unsigned long clone_flags)
+void fastcall sched_fork(task_t *p)
 {
-	int cpu;
-#ifdef CONFIG_SMP
-	struct sched_domain *tmp, *sd = NULL;
-	preempt_disable();
-	cpu = smp_processor_id();
+	int cpu = smp_processor_id();
 
-	if ((clone_flags & (CLONE_VM|CLONE_VFORK)) == CLONE_VM) {
-		/*
-		 * New thread that is not a vfork.
-		 * Find the largest domain that this CPU is part of that
-		 * is willing to balance on clone:
-		 */
-		for_each_domain(cpu, tmp)
-			if (tmp->flags & SD_BALANCE_CLONE)
-				sd = tmp;
-		if (sd)
-			cpu = find_idlest_cpu(p, cpu, sd);
-	}
-	preempt_enable();
-#else
-	cpu = smp_processor_id();
-#endif
 	/*
 	 * The task hasn't been attached yet, so cpus_allowed mask cannot
 	 * change. The cpus_allowed mask of the parent may have changed